OpenCart Community

Randomly when people place orders postage keeps being selected at the cheapest rate.

So I up to £5 is £1 postage, up to £10 is £2 and so on. Every now and then the postage is £1 regardless of what has been ordered... Any ideas why this would start happening?

OpenCart doesn't have total-based shipping built-in, so you must be using an extension. Contact the developer of that extension for support, since it's unlikely anyone in here will be able to help you with a commercial extension.

It's using the royal mail extension that came with opencart?

Royal Mail is weight-based, not total-based. So if you set a bracket like this:

5:1.00, 10:2.00

then that means charge £1.00 for up to 5 kg, and £2.00 for 5-10 kg. That's probably why you're having issues with your setup.

If you need an extension that can do total-based shipping costs, I have a Total-Based Shipping that will work for that. To get the setup you described, you'd enter your brackets like this:

0-5.00 = 1.00
5.01-10.00 = 2.00

Feel free to take a look at the screenshots and demo site, and if you're interested let me know at www.getclearthinking.com/contact if you have any further questions.